Background and Aim: Chronic hepatitis C virus (HCV) infection is relatively frequent in China. This study investigated the clinical, demographic, and viral and host genetic characteristics that may influence disease manifestations and clinical management. Methods: In this cross-sectional observational study, treatment-naïve Han ethnic adults with recently confirmed chronic HCV infection were enrolled at 28 hospitals across China. HCV genotype and host interleukin 28B (IL28B) genotypes were determined and compared with patient demographic parameters and medical status. Results: Among the 997 HCV-positive patients analyzed, 56.8% were infected with HCV genotype 1b, followed in prevalence by genotypes 2, 3, and 6, with substantial regional variation. Overall, 84.1% of patients were IL28B genotype CC (rs12979860), with little regional variation. Cirrhosis was reported in 10.1% of patients and was significantly associated with hepatitis B virus coinfection, low HCV viral load, low serum alanine aminotransferase, high serum aspartate aminotransferase, diabetes, and high pickled food consumption. Medical procedures were common transmission risk factors; however, lifestyle-associated risk factors, including intravenous drug abuse and tattoos or piercings, were more common in patients with HCV genotype 3 or 6. Conclusions: Most HCV-infected Han Chinese patients were IL28B genotype CC (rs12979860). HCV genotypes varied by geographic region, and disease characteristics differed according to HCV genotype. Relatively frequent detection of advanced liver disease may reflect limitations on access to antiviral therapy, and suggests that greater awareness of factors that influence HCV-associated disease may help avoid clinical complications and improve patient outcomes.

White spot syndrome virus (WSSV) is a major shrimp pathogen causing large economic losses. In an attempt to identify the envelope proteins involved in virus infection, antisera against six WSSV envelope proteins were used in neutralization assays conducted in vivo. The results showed that the virus infection could be significantly delayed or neutralized by antibodies against three WSSV envelope proteins (VP68, VP281 and VP466). This neutralization was further confirmed by quantitative PCR. It could be concluded that the viral envelope proteins VP68, VP281 and VP466 played roles in WSSV infection to shrimp.

Dear Editor, The ongoing COVID-19 pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has resulted in unprecedented public health and socioeconomic crises, requiring urgent developments of effective COVID-19 therapeutics and vaccines. Humoral immunity is essential for protection against coronavirus infections and passive immunization has been demonstrated to be effective in curing SARS-CoV-2-challenged nonhuman primates. 1,2 A deep understanding of the molecular basis of neutralizing antibody (NAb) responses to SARS-CoV-2 could facilitate vaccine design and drug discovery. Spike (S) protein, the major protective antigen, utilizes its receptor-binding domain (RBD) to engage the host receptor ACE2 for viral entry into host cell. Subsequently, a number of RBD-targeting NAbs against SARS-CoV-2, which block the binding of S to ACE2 have been reported and characterized. 2-5 However, a major concern is the emergence of numerous viral mutations within RBD, in particular, when selective pressure is applied in immunotherapies, resulting in resistance against these antibodies. Recently, two antibodies targeting N-terminal domain (NTD) of S exhibited potent neutralizing activities against SARS-CoV-2. 6,7 When used in combination with RBD-targeting and NTD-directing NAbs, the protective effect was magnified. 5,6 Thus, a combination of antibodies could not only increase the potency of protection, but also prevent viral escape of immune responses via mutations. These preliminary results highlight the benefits of using a cocktail of antibodies for treating COVID-19 and provide a framework for rational design of antibody cocktail therapeutics that target both RBD and NTD regions. Furthermore, the structural characterizations of S in complex with potential NAb cocktails reported recently inform strategies for the development of vaccines for protection against COVID-19. Successful antibody cocktail therapeutics for Ebola were generated by mixing NAbs from humanized antibodies from mice and human survivors. This indicates that NAb diversity plays critical roles in the design of antibody cocktails, and that this diversity can be achieved through various approaches. We have recently described parallel efforts, involving use of humanized antibodies developed from libraries of mouse origin and antibodies screened from libraries constructed from peripheral blood mononuclear cells (PBMCs) of convalescent humans. A large collection of highly potent NAbs targeting both RBD and NTD of SARS-CoV-2 S protein were obtained. 3-6 Among these, two humanized RBD-targeting NAbs, named H014 and HB27, are pan-SARS-CoVs cross-reactive and SARS-CoV-2-specific NAbs, respectively. 3,4 The other two fully human NAbs, FC05 and P17, recognize NTD and RBD of S, respectively. 5,6 All four NAbs individually exhibited potent neutralizing activities at sub-nM concentrations and conferred effective protection against SARS-CoV-2 in animal models. 3-6 These preliminary results allowed us to rationally design two-antibody cocktails of the N...